Search results
Results from the WOW.Com Content Network
A tuff cone, sometimes called an ash cone, is a small monogenetic volcanic cone produced by phreatic (hydrovolcanic) explosions directly associated with magma brought to the surface through a conduit from a deep-seated magma reservoir. They are characterized by high rims that have a maximum relief of 100–800 meters (330–2,620 ft) above the ...
Lacking a central volcanic cone, the Svartsengi volcanic system consists of a set of fissures, cones and volcanic craters aligned over 30 km (19 mi) in length and 7 km (4.3 mi) in width, oriented north-east to south-west and surrounded by fields of lava: [3] Þorbjörn (243 m (797 ft)), Hagafell (158 m (518 ft)), Sundhnúkur 134 m (440 ft) (Sundhnúksgígar means the associated crater row ...
A cinder cone (or scoria cone [1]) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. [ 2 ] [ 3 ] The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent.
In volcanology, a Strombolian eruption is a type of volcanic eruption with relatively mild blasts, typically having a Volcanic Explosivity Index of 1 or 2. [1] Strombolian eruptions consist of ejection of incandescent cinders, lapilli, and volcanic bombs, to altitudes of tens to a few hundreds of metres. The eruptions are small to medium in ...
A rootless cone at Myvatn Lake, Iceland. A rootless cone, also formerly called a pseudocrater, [1] is a volcanic landform which resembles a true volcanic crater, but differs in that it is not an actual vent from which lava has erupted. They are characterised by the absence of any magma conduit which connects below the surface of a planet.
Ol Doinyo Lengai is an active volcano in northern Tanzania. It consists of a volcanic cone with two craters, the northern of which has erupted during historical time. Uniquely for volcanoes on Earth, it has erupted natrocarbonatite, [3] an unusually low temperature and highly fluid type of magma. Eruptions in 2007–2008 affected the ...
The Mount Edziza volcanic complex is a linear group of volcanoes in northwestern British Columbia, Canada. [8] [9] It is about 65 kilometres (40 miles) long and 20 kilometres (12 miles) wide, consisting of several stratovolcanoes, shield volcanoes, subglacial volcanoes, lava domes and cinder cones.
The volcano partly overlaps with two older volcanoes, Baruta and Shaheru, and is also surrounded by hundreds of small volcanic cinder cones from flank eruptions. [citation needed] Nyiragongo's cone consists of pyroclastics and lava flows. [6] Nyiragongo's lavas are low-silica, alkali-rich, ultramafic extrusive rocks essentially free of feldspars.